Actuator

ABSTRACT

The invention provides an actuator apparatus which may be used to adjust flow of fluid or air in conjunction with a rack and pinion system. The device is able to rotate both vertically and horizontally via a mechanism that transforms axial movement into rotary movement. The device is useful in a range of circumstances where required specific and controllable rotary motion is required.

FIELD OF THE INVENTION

The invention relates to an actuator that uses an adjustable flowhydraulic or pneumatic cylinder operating through a rack and pinion.This in turn, powers devices such as cannons (sometimes known asmonitors), more preferably fluid cannons.

BACKGROUND

A liquid cannon is normally a tubular device which can be rotated bothhorizontally and vertically to control the direction of water flow froma nozzle. In operation, one end of the device is connected to a groundsourced water supply or mobile tank. The other end of the deviceterminates in a nozzle, which is used to project the fluid out of theliquid monitor in a desired direction, speed and volume. The liquidsupply is typically under a pressure, thereby inducing a forcefulprojection of fluid out of the nozzle of the liquid cannon.

A liquid cannon can typically be articulated, such that the direction offluid projection may be changed about both a vertical axis andhorizontal plane, to enable the projection of water to be aimed indifferent directions. A liquid cannon is used by its operator to projecta volume of fluid onto or into a variety of locations for dustsuppression, fire fighting or surface cleaning. Many liquid cannons areattached directly to a vehicle, such as a water truck.

Known cannons have a number of disadvantages.

Many lack simplicity of design. The system often needs to be repaired bysemi skilled personnel working in remote locations which have poorengineering support. This also extends to the power mechanism for anyrotational movement. The fewer motors and pumps the vehicle has the lesslikely they will be to break down and the easier they will be tomaintain and keep operational. Simplicity is also a key to operationaladjustments or changes. The unit needs not only to be easy to maintainbut also easy to adjust should any performance changes be required i.e.rotational movement speed increased or reduced. It also needs to betolerant of harsh environments and vibration, both of which are verycommon in off road situations.

Cannons may require remote activation by an operator. This allows thecannon to be located in the best position relative to the destinationfor the liquid but at the same time gives flexibility for the operatorto be wherever he/she needs to be. In the case of a water truck theoperator is located in the cab driving the vehicle so the cannon needsto be operated from this location.

The control mechanisms need to be unaffected by the presence of liquidsand water in particular. Electronic actuating mechanisms are thereforeless desirable as they have a tendency to corrosion and short circuitswhen water is present.

The pressure with which fluid is forced from the nozzle placessignificant stress on any rotating actions (moving parts controllingslew and elevation need to be robust). Many previous rotating mechanismshad a very short service life due to their actuating mechanism designand fabrication.

Cannons need to be economic to manufacture. The nature of water truckoperations especially requires a cannon to be economic to produce andsupply to the industry.

Known liquid cannons do not provide these features and there istherefore a need for an improved actuating mechanism that provides thepublic with a more reliable system.

OBJECT OF THE INVENTION

It is an object of the invention to provide an actuating mechanism for acannon that has advantages over known systems or which will at leastprovide the public with a useful choice.

SUMMARY OF THE INVENTION

The invention provides a pneumatic or hydraulically powered actuatorapparatus which is adapted for cannon type applications wherein, therequired rotary motion in the actuator apparatus is transmitted to thecannon type application via a rack and pinion mechanism, in conjunctionwith a cylinder and reduction set.

Specifically the invention provides an actuator apparatus adapted for acannon type application delivering required rotary motion at theactuator apparatus output, and wherein the drive train of the apparatustransforms axial movement into rotary movement.

Specifically the invention provides an actuator apparatus comprising arack and pinion mechanism in combination with a cylinder and reductiongear set. The drive train transforms axial movement into rotarymovement.

The cylinder and reduction gear set is preferably made from corrosionresistant stainless steel and brass components.

Preferably the actuator includes an integral adjustable flow controlvalve (needle valve) which allows for a simple and easy flow adjustmentcontrolling speed and “feel”.

In the case of a fluid cannon, the cannon's base may be held onto afixed surface and a tubular body rotates horizontally on this base. Thetubular body then preferably bends 180 degrees and affixes to anothertubular body which rotates vertically to aim the fluid where it is to besprayed.

The vertical and horizontal rotations are preferably powered eitherhydraulically or pneumatically via adjustable flow cylinders through theuse of the rack and pinion and gear set.

The cylinders may be remotely controlled by a human operator moving anelectronic joystick which actuates solenoid valves to direct oil or airto rams to provide the required rotational movement.

The rotational movement may be provided via electric over air orelectric over hydraulic.

The invention also provides an actuator apparatus comprising:

(a) a horizontal drive apparatus operatively engaged with a rotatablebody, the horizontal drive apparatus being operable to rotate therotatable body in response to control signals;

(b) a vertical drive apparatus operatively engaged with a dischargeelbow, the vertical drive apparatus being operably able to rotate saiddischarge elbow in response to control signals.

This provides a 360 degree movement of a cannon for precisely directedfluid flow. Both the horizontal and vertical drive apparatus form thebasis of the invention and use a rack and pinion mechanism inconjunction with a gear set. This drive train transforms the axialmovement of the pistons into a rotary movement required to operate thecannon. The piston actuates in the desired direction when a joystickactivates the relevant solenoid and air or fluid is directed to thedesired end of the cylinder. The piston moves axially and this movementis transferred via a rack and pinion to rotate the pinion. The rackpreferably forms part of the cylinder piston shaft. This rotary movementof the pinion is further geared down using a gear set comprising of onesmaller gear (driver) attached to the end of the pinion and one largergear (driven) attached to the portion of the cannon which is to berotated. The speed transmitted by the rack and pinion and gear set maybe adjusted by changing the teeth on the rack and pinion or gear setsand the hydraulic or pneumatic force may also be changed by altering thepiston size.

Preferably the actuator comprises a series of electric over air or oil(dependant on whether the system is pneumatic or hydraulic) solenoidswhich control the piston's movement and receive their instructions froman electronic joystick which is controlled by the machine operator. Eachrotating member (one vertical [elevation] and one horizontal [slew]) maybe controlled by an individual cylinder, and these in turn may becontrolled by the joystick's movement and the resulting actuation of thesolenoids. The solenoid directs oil or air under pressure to therequired end of the cylinder while at the same time exhausting oil tothe reservoir or air to atmosphere from the other end of the cylinder.

The invention also provides an actuator apparatus for conveying anddirecting a fluid to a desired location comprising:

(a) a base element having a first hollow conduit formed there through,said first conduit having a first end and a second end, said first endadapted to be connected to a source of fluid;

(b) a rotatable body mounted to the base element, the rotatable bodyhaving a second hollow conduit formed through it, the second conduithaving a first end and a second end, the first end of the second conduitcommunicating with the second end of the first hollow conduit, therotatable body capable of rotation about a horizontal axis through aninfinite arc; and

(c) a discharge elbow rotatably mounted to the rotatable body, thedischarge elbow having a third hollow conduit formed through it, thethird conduit having a first end and a second end, the first end of thethird conduit communicating with the second end of the second conduit,the second end of the third conduit terminating at a discharge openingwhich directs discharge of the fluid in a desired direction, thedischarge elbow being capable of rotation about a vertical axis throughan arc of 280 degrees.

The invention which assists in rotating the cannon in a vertical andhorizontal plan, is particularly helpful in powering water or liquidcannons, and specifically to liquid cannons used for such things asconstruction site dust suppression, cleaning of equipment,fire-fighting, or sluicing in which the ability to control the directionof flow of water from the monitor is required to be compact, robust andeconomic to construct.

The invention also provides, by the nature of the stainless steel andbrass material used in its construction, for a very corrosion resistantand long lasting apparatus. These materials enable the actuator tosuccessfully operate in corrosive and unfriendly environments where saltwater or other atmospheres may prematurely fail other materials.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a cutaway view of the actuator mechanism. It shows the ports(1 or 2), the cylinder (6), piston (3 or 4), needle valve (8), rack (10)and pinion (7) and the driven (9) and driver gears (5). From thispicture one can see the basic principal of our patent.

FIG. 2 is a schematic depiction of the hydraulic/pneumatic flows fromthe electronic control valve to the cylinder and the fluid effect of theneedle valve.

FIG. 3 is a see through pictorial view of the basic components of theinvention.

FIG. 4 a-e shows the cylinders in more detail specifically theconnection to the rotating assembly.

FIG. 5 shows the cylinder fully extended to the left.

FIG. 6 shows the movement of the rack and piston with the associatedtransfer of fluid from the inside of the piston on the left to theinside of the piston in the right.

FIG. 7 shows internal view of one side of the cylinder.

FIG. 8 shows two actuators fitted to a typical fluid cannon requiringboth vertical and horizontal rotating movement.

The invention will now be described, by way of example only and withreference to the drawings.

DETAILED DESCRIPTION

The actuator apparatus shown in FIG. 1 shows a cylinder (6), pistons (3and 4), a needle valve (8), a rack (10) and pinion (7) and driven (9)and driver (5) gears.

In the schematic representation in FIG. 2 the control valve is picturedin the neutral position with no air or fluid flow to either end of thecylinder (6). If the solenoid control valve (14) is moved to the leftthen pressure air or fluid is directed to the right hand side of thecylinder (6) and air or fluid is exhausted from the left side of thecylinder (6) back through the solenoid control valve (14) to thereservoir if oil or atmosphere if air. FIG. 2 also shows theincompressible fluid chambers (12).

The basic components of the invention can most clearly be seen in FIG.3. This diagram shows the cylinder (6), piston (3 or 4), rack (10),pinion (7), driven (9), driver (5) gears and fluid chamber 12.

The cylinders are shown in more detail in FIG. 4 where especiallyvisible are the cylinders and their connection to the rotating assembly.Pistons (3) and (4), fluid chamber (12), driver gear (5), needle valve(8) and driven gear (9) are shown.

A fully extended cylinder is shown in FIG. 5 pistons (3 and 4), the rack(10) and the fluid chamber (12) are shown.

FIG. 6 shows the movement of the rack and piston to the right with theassociated transfer of fluid from the inside of the piston on the leftto the inside of the piston in the right. Also shown is the fluidchamber (12) and the needle valve (8).

FIG. 7 shows an internal view of one side of cylinder; piston (3 or 4),pinion (7), needle valve (8), rack (10).

FIG. 8 shows how two actuator mechanisms can be fitted to a typicalfluid cannon that requires both vertical and horizontal movement. In thediagram, the needle valve (8) and the cylinders (6) can be seen.

The actuator as described can perform a variety of actuating functionsaccording to need but in this description the use of the actuatorrelating to the rotating action (vertical and horizontal) of a fluidcannon on a water truck is described. It will be appreciated howeverthat the actuator apparatus described may be used in a number ofsituations, where speed control of vertical and horizontal movement isrequired, along with protection from vibration and contamination fromthe environment.

The actuator may be powered by hydraulic oil under pressure or bycompressed air (pneumatic).

An operator of the actuator apparatus switches the desired electricalswitch in the control centre. This electrical switch in turn activatesthe desired solenoid to direct air or fluid to the required cylinder (6)(an electric over air or electric over fluid solonoid). The cylinder (6)will either operate the slew or the elevation cylinders. Eitherhydraulic oil pressure (from an independent oil pump) or air pressure(from an independent air compressor) will then be directed to thespecified actuator.

Hydraulic oil or air enters the cylinder (6) via an port (1 or 2),dependant on which way the actuator is to move. The pressurised air orfluid acts against the surface of the piston (3 or 4) and moves thepiston and therefore the rack (10) within the cylinder (6) to the leftor right. The rack (10) has teeth which are meshed with the teeth of thepinion (7). The movement of the rack (10) to the left or right resultsin the pinion rotating either clockwise (if the rack (10) moves fromleft to right) or anticlockwise (if the rack (10) moves from right toleft). The axial movement of the pistons (3 and 4) and the rack (10) arethereby transformed into rotary movement using the meshing and impartingmotion of the rack (10) and pinion (7) gears.

Concurrently, the needle valve (8), which is positioned in the fluidconnecting passage between the inner areas behind each of the pistons,meters the bypass of the fluid from the inner side of the piston on oneside to the inner side of the piston from the other side. This meteringeffect results in a dampening action of the piston's movement. This isone method for controlling piston speed and giving a steady andpredictable feel to the required movement. The extent of travel for therack and therefore the rotation of the pinion is determined by eitherthe operator and the joystick (releasing the joystick back to theneutral position) or when the piston contacts either end of thecylinder.

With reference to FIG. 1, it can be seen that the rotary movement of thepinion shaft is transferred to the connected driver gear (5) (fixed tothe shaft). The driver gear (5) then drives the driven gear (9). Thedriven gear (9) is directly connected to the output member of therotation device and thus transfers the rotation to this member. In thecase of the fluid cannon, the output member is directly connected to therotation of the slew (horizontal) motion of the cannon or the elevation(vertical) motion of the cannon and the rotation of these parts isdetermined by the action of the whole actuating mechanism.

The invention's basic components and their relativity to each other ismost easily seen in FIG. 3. If the motion flow is followed from thepistons to the rack and its teeth meshed with the pinion shaft, this inturn rotates the smaller driver gear which finally rotates the largerdriven gear.

Although other advantages may be found and realized and variousmodifications may be suggested by those versed in the art, it isunderstood that the present invention is not to be limited to thedetails given above, but rather may be modified within the scope of thespecification.

The actuating mechanism according to the invention provides a number ofadvantages over the known mechanism. For example, the design and buildis extremely simple and yet very robust. It is ideally suited to extremeapplications and will tolerate very dirty environments and is notvibration sensitive. It is likewise not sensitive to the effects ofwater or contamination.

The design concept allows for an almost infinite variation of speed,control and force applied from the actuating cylinder. By changing thesize of the rack and pinion teeth, or the number of the driving anddriven teeth, the speed of rotating member can be varied. By changingthe size of the piston the turning force can be further changed and afurther torque multiplication on the rotating member can occur; furtherif the pistons are unequal sizes on each side of the actuating cylinder,different forces can be applied in differing directions. This allows fordifferential forces to be applied for different applications requiringthis.

The cylinder has an integral needle valve which limits the rate at whichthe fluid on the inside of one piston is able to transfer to the otherside of the cylinder. This effectively creates a variable damper whichenables the actuator to operate faster or slower simply by theadjustment of an external needle valve.

The actuator is remotely controlled through solenoids activated by theoperator using electronic switches. This allows remote control of theactuator while using air or fluid to activate it, this allows for theunit to be used in extreme conditions and in circumstances whereprimarily electrical systems are likely to fail.

Whilst the invention has been described with reference to a particularembodiment, it will be appreciated that numerous modifications andimprovements may be made to the embodiment without departing from thescope of the specification as set out in the description.

For example, the specific embodiment described relates to a fluidcannon, more particularly a water cannon. It is envisaged however thatthe invention could be applied to many mechanical devices requiringrobust actuating mechanisms capable of remote control and able tooperate in wet, dirty and harsh environments, examples of applicationswould be;

-   -   Remote rotation and actuation of small armament;    -   Remote control of some agricultural components i.e., combine        harvester auger arm movement;    -   The controlled raising and lowering of front or rear mounted        specialist implements on specialist vehicles i.e., mobile spray        equipment or horticultural machinery;    -   The control and actuation of marine equipment i.e., winches        where corrosion and salt water are problematic;    -   Remote operation of gate or fluid valves in harsh environments.

INDUSTRIAL APPLICABILITY

The invention will find a wide range of industrial applications incannons where a robust actuating mechanism is required. This may be in,for example, armament vehicles, agricultural mechanisms, and marineequipment.

1. An actuator apparatus adapted for a cannon type application andconfigured to deliver a required rotary motion at an actuator apparatusoutput, the actuator apparatus comprising a drive train that transformsaxial movement into rotary movement.
 2. An actuator apparatus accordingto claim 1 wherein, the required rotary motion in the actuator apparatusis transmitted to the cannon type application via a rack and pinionmechanism, in conjunction with a cylinder and reduction set.
 3. Anactuator apparatus according to claim 1 or claim 2 which ispneumatically or hydraulically powered.
 4. An actuator apparatusaccording to claim 2 in which the cylinder and reduction set is madefrom corrosion resistant stainless steel and brass components.
 5. Anactuator apparatus according to claim 1, 2 or 4 in which the actuatorapparatus further includes an integral control valve to allow for flowadjustment of a fluid from the cannon type application.
 6. An actuatorapparatus according to claim 2 or 4 in which the cannon type applicationis a fluid cannon.
 7. An actuator apparatus according to claim 6 inwhich the fluid cannon is a water cannon.
 8. An actuator apparatusaccording to claim 6 in which a base of the fluid cannon is attached toa fixed surface and wherein the fluid cannon rotates horizontally on thebase.
 9. An actuator apparatus according to claim 8 in which the fluidcannon is adapted to be rotated both vertically and horizontally.
 10. Anactuator apparatus according to claim 9 in which the fluid cannonincludes a first tubular body and a second tubular body, wherein thefirst tubular body is adapted to bend at an angle of 180 degrees and isaffixed to the second tubular body which rotates vertically to thuscontrol the direction of aim of a fluid from the fluid cannon.
 11. Anactuator apparatus according to claim 10 in which the horizontal andvertical rotations of the fluid cannon are powered either hydraulicallyor pneumatically via adjustable flow cylinders through the use of therack and pinion mechanism.
 12. An actuator apparatus according to claim11, the actuator apparatus operable by an electronic joystick whichactuates a solenoid valve to direct oil or air to at least one of theadjustable flow cylinders to provide the required rotational movement.13. An actuator apparatus according to claim 1, and further comprising:(a) a horizontal drive apparatus operably engaged with a rotatable body,the horizontal drive apparatus being operable to rotate the rotatablebody in response to control signals; (b) a vertical drive apparatusoperably engaged with a discharge elbow, the vertical drive apparatusbeing operable to rotate said discharge elbow in response to the controlsignals; and (c) at least one of the horizontal drive apparatus or thevertical drive apparatus includes the drive train.
 14. An actuatorapparatus according to claim 1, further comprising: (a) a base elementincluding a first conduit formed therethrough, said first conduitincluding a first end and a second end, said first end adapted to beconnected to a source of fluid; (b) a rotatable body mounted to the baseelement, the rotatable body including a second conduit formed throughit, the second conduit including a first end and a second end, the firstend of the second conduit communicating with the second end of the firstconduit, the rotatable body capable of rotation about a horizontal axisthrough an arc; and (c) a discharge elbow rotatably mounted to therotatable body, the discharge elbow including a third conduit formedthrough it, the third conduit including a first end and a second end,the first end of the third conduit communicating with the second end ofthe second conduit, the second end of the third conduit terminating at adischarge opening which directs discharge of the a fluid in a desireddirection, the discharge elbow being capable of rotation about avertical axis through an arc of 280 degrees; and (d) the drive trainoperatively associated with at least one of the rotatable body or thedischarge elbow.
 15. A cannon comprising: a first actuator apparatusincluding a first drive train that transforms axial movement into arotary output.
 16. A cannon according to claim 15 further comprising asecond actuator apparatus including a second drive train that transformsaxial movement into a rotary output.
 17. A cannon of claim 15, whereinthe first drive train comprises a rack and pinion mechanism and acylinder and reduction set.
 18. A cannon according to claim 15 or 17,wherein the first actuator apparatus is pneumatically or hydraulicallypowered.
 19. A cannon according to claim 17, wherein the cylinder andreduction set is made from steel and brass components.
 20. A cannonaccording to claim 15, 17 or 19, wherein the first actuator apparatusincludes an integral control valve to allow for flow adjustment of afluid from the cannon.
 21. A cannon accordingly to claim 17 or 19,wherein the cannon includes a base attached to a fixed surface and thecannon rotates horizontally on the base.
 22. A cannon according to claim21, wherein the cannon is further configured to rotate vertically.
 23. Acannon according to claim 22, further comprising a first tubular bodyand a second tubular body, wherein the first tubular body is configuredto bend at an angle of 180 degrees and is affixed to the second tubularbody which rotates vertically to thus control the direction of aim of afluid from the cannon.
 24. A cannon according to claim 23 in which thehorizontal and vertical rotations of the cannon are powered eitherhydraulically or pneumatically via adjustable flow cylinders through theuse of the rack and pinion mechanism.
 25. A cannon according to claim24, wherein the actuator apparatus is operable by an electronic joystickwhich actuates a solenoid valve to direct oil or air to at least one ofthe adjustable flow cylinders to provide the rotary output.
 26. A cannonaccording to claim 15, further comprising: (a) a horizontal driveapparatus operably engaged with a rotatable body, the horizontal driveapparatus operable to rotate the rotatable body in response to controlsignals; (b) a vertical drive apparatus operably engaged with adischarge elbow, the vertical drive apparatus operable to rotate saiddischarge elbow in response to the control signals; and (c) at least oneof the horizontal drive apparatus or the vertical drive apparatusincludes the first actuator apparatus.
 27. An actuator apparatusaccording to claim 15, further comprising: (a) a base element includinga first conduit formed therethrough, said first conduit including afirst end and a second end, said first end adapted to be connected to asource of fluid; (b) a rotatable body mounted to the base element, therotatable body including a second conduit formed through it, the secondconduit including a first end and a second end, the first end of thesecond conduit communicating with the second end of the first conduit,the rotatable body capable of rotation about a horizontal axis throughan arc; and (c) a discharge elbow rotatably mounted to the rotatablebody, the discharge elbow including a third conduit formed through it,the third conduit including a first end and a second end, the first endof the third conduit communicating with the second end of the secondconduit, the second end of the third conduit terminating at a dischargeopening which directs discharge of a fluid in a desired direction, thedischarge elbow being capable of rotation about a vertical axis throughan arc; and (d) the first actuator apparatus operatively associated withat least one of the rotatable body or the discharge elbow.